Phenotypic diversity and association analysis for traits related to salt tolerance in wheat

In order to evaluate variation and reaction of 40 wheat genotypes to salinity tolerance and assess the association of 27 microsatellite markers with salinity tolerance and morpho-physiological traits measured under normal and salt stress conditions, the present study was conducted. The results of analysis of variance in two environments showed significant difference among genotypes for all traits, indicating genetic variation among them. Based on the results of combined analysis of variance, the effect of the environment for all traits and the effect of Genotype × environment on most of the traits was significant and it was determined that the response of the evaluated genotypes to salinity stress was different In two environment, the highest variation was belonged to grain yield and its component and biological yield. Cluster analysis in salinity stress based on traits with significant genotype × environment, classified the genotypes into 3 groups i.e. tolerant moderate and sensitive. Association analysis using 27 microsatellite markers, SSR markers with 11 traits measured in two normal conditions and salinity stress for all genotypes was conducted through a mixed linear model (MLM) The study of population structure as a precondition for communication analysis showed that there are 2 probable subgroups (K = 2) in the population studied, which was confirmed by the results of the plot formula. The decomposition of the association analysis using 27 SSR markers with 11 traits measured in two conditions based on mixed linear model (MLM) was carried out using the population structure matrix. Based on the results, 29 locations had a significant relationship with the evaluated traits in the normal environment, while in the salinity stress environment, this number increased to 40 locations. The existence of common markers among some of the studied traits such as the significant associate between S16-1 and 3 traits in normal conditions and with 5 traits in the salinity medium can be due to the polytrophic effects of these markers and possibly the connectivity of genomic locations controlling these traits. S6-3 and S12-1 markers were identified as markers that associated with grain yield in salinity condition and S11-4 marker was identified as marker that related with biological yield in both environmental Conditions. Finally, given the results obtained, if the results are confirmed in other genetic fields, these markers can be used in corrective programs.